Debris collection systems typically include a receptacle for storing debris, an intake tube, and means for creating an airflow in the intake tube that draws or carries the debris through the conduit and into the receptacle.
The required airflow is generally created by either an air conveyance system or a vacuum system. Air conveyance systems create an air flow in the conduit which carries debris to the receptacle. Vacuum systems utilize a vacuum pump to create a partial vacuum in the receptacle. Vacuum systems have several advantages over those using air conveyance. For example, air conveyance units use an open exhaust system for their fan or compressor. When the receptacle is filled, contaminates are carried by the air flow system and discharged into the atmosphere, potentially polluting the air. In contrast, vacuum systems are generally completely sealed. When the receptacle is full, the system itself automatically reduces the vacuum to prevent discharge of contaminated material
Furthermore, vacuum units, by reason of the vacuum created in the receptacle, are capable of collecting both liquid and solid material. While air conveyance systems are capable of moving solid particulate debris, they are unable to draw up large amounts of liquid. Vacuum systems are well suited for liquid pickup since submerging the end of the intake tube below the water level maintains the vacuum in the system.